About how heme is catabolised

1. CATABOLISM OF HEME
Presented by:
S. Suryakumari
621149701046
B-Pharmacy 1st year
Maharajah’s college oPharmacy
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2. Degradation of Heme to Bile Pigments
▪ Erythrocytes have a life span of 120 days.
▪ These are taken up and degraded by macrophage of reticuloendothelial system in
SPLEEN and LIVER.
▪ HEME is converted into an yellow coloured BILIRUBIN pigment.
▪ Haemoglobin is cleaved into protein part GLOBIN and non- protein part HEME.
▪ FATE OF GLOBIN: Globin may be reutilized as such for formation of Hemoglobin (Hb) or
degraded to individual amino acids.
▪ SOURCES OF HEME: About 80% of heme that is subjected for the degradation comes
from the erythrocytes and rest from RBC, myoglobin and cytochromes.
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3. CATABOLISM OF HEME
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4. Significance:
• Abnormalities in heme synthesis cause porphyrias which may be
erythropoetic(enzyme defect in RBC) or hepatic(enzyme defect in liver).
• Jaundice is caused by elevated serum bilirubin (normal<0.8mg/dl) levels.
• It is characterized by yellow colouration of skin and whites of eyes.
• Thalassemia are hemolytic disoders caused by impairment or imbalance in the
synthesis of globin.
• Sickel cell haemoglobin causes hemolytic anemia, increased suspectibility to infection
and prematuredeath.
• Phototheraphy ( by exposure to blue light) is used to control severe causes of
neonatal physiological jaundice.
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